The Effect of Using CHP Systems in Energy Utilization and Reduction of Greenhouse Gases in a Plup and Paper mill in Iran
Home
Pulp and paper industries consume about 6% of the total energy used in the industries worldwide, and are
considered some of energy consuming industries. These mills are accounted as one of the attractive choices to implement combined heat and power system. In these industries, the production of steam, at high capacity, by boilers, is necessary for washing, refining and drying stage in the production of pulp and paper.
Pulp and paper industries consume about 6% of the total energy used in the industries worldwide, and are
considered some of energy consuming industries. These mills are accounted as one of the attractive choices to implement combined heat and power system. In these industries, the production of steam, at high capacity, by boilers, is necessary for washing, refining and drying stage in the production of pulp and paper.
In this study, the improvement of combined heat and power system operation was studied in an Iranian pulp and paper mill. In this plant, for the purpose of production of the required steam, two boilers were used. Due to non-conformity of conditions of steam produced by boilers (a pressure of 60 bars and temperature of 445oC) with the steam necessary for the process (a pressure of 12.2 bars and temperature of 200oC), the conversion of produced steam to consumed steam was done by using pressure-reducing valves and this sets the stage of considerable loss of energy. For this reason, the energy recovery potential and production of a portion of electrical energy needed by the plant using the backpressure steam turbine has been studied. In this study, four types of technologies in the utilization of steam turbine have been examined, with each technology being studied in three steam production strategies using thermo-economic analysis.
Results indicate that using above technologies and strategies, under most optimal conditions, reducing in natural gas consumption up to 50% and the equivalent of 41600 tons per year of carbon dioxide greenhouse gas is achieved.